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Updated: May 13, 2026
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Assessment of Submitochondrial Protein Localization in Budding Yeast Saccharomyces cerevisiae
Published on: July 19, 2021
Intramolecular interactions control Vms1 translocation to damaged mitochondria
Jin-Mi Heo1, Jason R Nielson, Noah Dephoure
1Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
Molecular Biology of the Cell
|March 8, 2013
Summary
Vms1 protein monitors mitochondrial health and is recruited to stressed mitochondria. This protein quality control mechanism is crucial for cellular survival and preventing age-related diseases.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Biology
Background:
- Mitochondrial dysfunction is linked to age-related diseases, making early detection critical.
- The VCP/Cdc48-associated mitochondrial stress responsive 1 (Vms1) protein is part of a surveillance system for mitochondrial protein degradation.
- Understanding Vms1's role is key to cellular welfare and survival.
Purpose of the Study:
- To elucidate novel mechanisms by which Vms1 monitors mitochondrial status.
- To investigate how Vms1 is recruited to damaged or stressed mitochondria.
- To define the cellular and biochemical control of Vms1 localization for protein quality control.
Main Methods:
- Identification and characterization of the Vms1 mitochondrial targeting domain (MTD).
- Analysis of Vms1 N-terminus regulation of MTD-mediated mitochondrial targeting.
- Utilizing laser-induced mitochondrial reactive oxygen species to study Vms1 recruitment under oxidative stress.
Main Results:
- Vms1 contains a conserved MTD essential and sufficient for mitochondrial targeting.
- Vms1's mitochondrial import is negatively regulated by its N-terminus interaction.
- Vms1 shows preferential recruitment to mitochondria experiencing oxidative stress.
Conclusions:
- Vms1 localization is tightly controlled by its MTD and N-terminus.
- Oxidative stress triggers Vms1 recruitment to damaged mitochondria.
- These findings reveal mechanisms for Vms1's role in mitochondrial protein quality control.
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